In planting most forms of vegetation such as trees, bushes, flowers, ground cover, bulbs, seeds and the like, the best results are obtained by surrounding the plant roots or the seed with loosely packed soil to promote root growth. If the surrounding soil is too hard packed, the plant can become root bound. However, the soil is often hard packed at locations where planting is desirable. One solution to this problem has been to form an oversized hole, pulverize the hard packed soil removed to make the hole and loosely pack the pulverized soil around the roots or the seed during the planting process. It is especially important for there to be a thick layer of pulverized soil underneath the plant, when a deep root system is desired.
Before the development of powered garden tools and landscaping equipment, such vegetation was planted by hand, typically using a shovel or the like to dig out a suitably sized hole in the ground to accommodate the plant or seed and the pulverized soil. Pulverizing soil by hand is very laborious and time consuming. With today's powered gardening tools and landscaping equipment, forming an oversized hole and producing sufficiently pulverized soil has become significantly less labor intensive and time consuming. However, even with present power tools and equipment, there is still a need to reduce the manual labor and time associated with the planting process.
One prior hole forming device, as disclosed in U.S. Pat. No.5,113,952, includes an auger bit with a single continuous flighting for use with a hand-held power tool such as a drill. The auger bit disclosed in the '952 patent bores a hole in the ground for planting flower bulbs and the like, pulverizing the soil in the process. A substantial amount of the pulverized soil is removed from the hole by the action of the continuous flighting. Since it is desirable for a thick layer of pulverized soil to surround the plant roots or seed, especially when the surrounding soil is hard packed, a substantial portion of the removed pulverized soil must be put back in the hole. This refilling step is labor intensive and adds to the time needed to perform the planting operation. Therefore, there is a need for a planting apparatus that pulverizes the soil as it forms a planting hole in the ground and at the same time is capable of leaving a substantial portion of the pulverized soil in the hole.
U.S. Pat. No.4,323,019 discloses an apparatus for planting tree seedlings or the like which pulverizes the soil as it bores a hole in the ground and includes a tubular support stand for keeping virtually all of the pulverized soil in the planting hole as it is being formed. However, this device is disclosed as being limited to planting tree seedlings and the like. In addition, this apparatus is relatively expensive to manufacture because of its complex structure. Therefore, there is also a need for a more versatile yet inexpensive alternative to the apparatus disclosed in the '019 patent.